Covering a flat roof will be different from a traditional sloped roof for many reasons including the materials required. While a pitched roof can use overlapping shingles or tiles, this method is likely to lead to leaking for a roof without any slope. There are many different materials and methods to installing a flat roof, including rubber, thermoplastic, tar and gravel and modified bitumen, but which one is best?
Rubber membranes such as EPDM (ethylene propylene diene terpolymer) are often applied in giant custom sized sheets to fit your flat roof. This material is durable, and the custom size limits the areas where a leak could occur. This kind of rubber can be more expensive than other materials.
Thermoplastic materials such as PVC (polyvinyl chloride) or TPO (thermoplastic olefin) are durable options, due to heat-welded seams, and offer improved energy efficiency. However, roofs made of these materials can be difficult to repair.
Tar and gravel are used in the Built-Up Roof (BUR) method. While this is typically a cheaper way to cover a roof, it can be heavy and messy to install and is usually accompanied by a strong odor. If you get a leak in this kind of roof, it may be hard to detect where it started.
Using modified bitumen on a flat roof can help save on costs as compared to newer technologies. The installation process can be very time-consuming and labor-intensive due to the number of layers and roll-on method of installation. It can also be difficult to detect the origin of leaks in a modified bitumen roof.
All materials have advantages and disadvantages. When choosing the flat roof roofing material that is best for your needs, you should consider building requirements, energy efficiency, budget and durability. Many believe that rubber is the best, but a licensed and trained roofing contractor can help you identify the ideal solution for your project.